I'm not exactly sure, but to answer the OP's question, I think Alpine made the professional hifi system in the e90. Below is a pic from one I ran across on eBay.

Harmon Kardon made the premium sound system (the step above the professional hi-fi). If I understand correctly Logic 7 is the DSP technology that Harmon used and in the early e90's (06-10) BMW marketed it as Logic 7 insted of Harmon Kardon. Same diff although I guess the technology in the newer units might sound better.